Air-compressor.



No. 684,954. Pa tented Oct. 22, mom.

I H. STRATER.

AIR COMPRESSOR.

- (Applicafiion filed Mar. 16, 1901.) (H Model.) 2 Sheets-Sheet I.

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NITED STATES PATENT OFFICE.

HERMAN STRATER, OF BOSTON, MASSACHUSETTS.

AIR-COMPRESSOR.

SEEGIFICATION forming part of Letters Patent N 0. 684,954, dated October22, 1901.

' Application filed March 16, 1901.

To all whom it may concern:

Be it known that I, HERMAN STRATER, a citizen of the United States, anda resident of Boston, countyof Suffolk, and State of Massachusetts, haveinvented an Improvement in Air-Compressors, of which the following de-jscription, in connection with the accompanying drawings,is aspecification, like characters on the drawings representing like parts.

This invention relates to hydraulic aircompressors of the type wherein aliquid, such as water, is used as the compressing agent, the valvescontrolling admission and discharge of the liquid to and from thecompressin -chamber being automatically operated by or through theagency of a float within the said chamber.

One of the objects of my present invention is to provide simpler,stronger, and more powerful means for actuating the valves with a quickopening or closing of the latter, as the case may be.

Another object of my invention is the practical utilization of thefioatas a controller for the valve-actuating mechanism, the latter includinga powerful hydraulic motor, and in order to provide for the quick andeli'estive operation of the latter I have provided fora difference inpressu re between the liquid-compressing agent as it is admitted to thecompressing-chamber and the motor,respectively, so that the shutting andopening of the admission and discharge valves will be practicallyinstantaneous, no matter what the pres sure of the liquid.

Various novel features of my invention will be fully describedhereinafter and particularly pointed out in the following claims.

Figure 1 is a vertical sectional view of the air-compressing chamber ofan apparatus embodying my invention, the automatic means for controllingthe inlet and outlet of the liquid for effecting air-compression beingshown partly in elevation and partly in section. Fig. 2 is a verticalsectional view of the valve-actuating motor viewed from the back of theapparatus. Fig. 3 is a detail in elevation of the cylinder forming apart of such motor, with the valve-ports thereof to be described. Fig. 4is a detached detail in elevation of the valve and valve-chest, and Fig.5 is an enlarged vertical sectional view showing the main inlet-passagefor the liquid and. the outlet-passage for the exhaust from the motor.

I Referring to Fig. 1, a compressing-chamber A is-shown, preferably ofthe general shape shown to permit the operation of devices, hereinafterto be described, which are contained in the chamber, the latter having adome-shaped upper portion and being mounted upon a base A, which hasextended through it a discharge-conduit a, the upper open end of whichforms a discharge-port a for the chamber, said conduit opening into aliquid seal or trap T of suitable construction and communicating withthe main discharge or waste pipe or conduit T in such a manner that thelevel of the liquid L in the trap will always be above the lower end ofthe conduit a, thus preventing the passage of any foul'air to thecompressing-chamber or of any air admitted through the Waste-pipe T. q

A supply-pipe S is connected by a suitable coupling S, Fig. 1, with thelower end of an inlet-condiiits,forn1ed in a standard or pipe B,

secured to the base A and extended up'into p the chamber, the upper endof the standard or pipe being bent over, as at B, and provided with aseat I) for a pressure-reducing valve b of any suitable construction,said valve being held against its seat by a spring 3 Fig. .1, the outerend of the spring being held in place by a cap I), tightly closing theend of the overhang B. The overhang at its under side and directly abovethe dischargeport a is provided with an admission-port 11 a ring-likevalve-seat I) being suitably secured to a nipple b on the overhang bymeans of a coupling b The compressingliquid, which may be and preferablywill be water, is admitted to the chamber A through the admission-port bthe inlet-pipe S being connected to a watersupply having a suitablehead-such, for example, as ordinary city waterthe gradual accumulationof the water in the chamber compressing the contained air in the domethereof,the air so compressed passing through an outlet-passage a andnozzle of to any suitable storage-receptacle or to the apparatus whichis to utilize the compressed air, a checkvalve a of any suitableconstruction preventing the return of the compressed air to the chamber.After the air has been compressed to the desired extent the admissionport will be closed and the outlet-port a opened by means to bedescribed, permitting the liquid in the chamber to flow out, and at thesame time fresh air will flow into the chamber through an air-inlet a asuitable check-valve a permitting the inlet of fresh air, but preventingthe escape of compressed air during compression.

Valves V V cooperate, respectively, with the admission and outlet ports,and I have herein provided novel and powerful valveactuating mechanismto close and open said ports at the proper times, said mechanismincluding a hydraulic motor. The motor comprises, essentially, acylinder 0, having a piston-rod c, which passes through suitablestuffing-boxes in the cylinder heads or ends and is rigidly connectedwith the valves V V, as clearly shown in Fig. 2, the cylinder havingports 3 -.t at opposite ends thereof com- 111 unicating at their otherends with the interior of a valve-chest 0'.

Referring to Fig. 3, the extension c of the cylinder-casting has theports or passages 3 and 1- therein, as well'as an exhaust-passage 0',one end or port being shown at 5 and the other end thereof at 6. issecured to the extension 0 by suitable bolts 7, Fig. 5, and the chamber0 0E the said chest contains the valve 0 best shown in Fig. 4 assegmental in shape and rigidly secured to an oscillating spindle c, thevalve having a recess 0 therein, adapted to establish communicationbetween the exhaust-port 5 and one or other of the cylinder-ports 3 4E,according to the position of the valve. The valve is provided with anextension or lug c, Fig. 4, which plays in a recess 0 in the wall of thevalve-chamber to positively limit the throw of the valve, thevalve-spindle 0 being extended through the wall of the extension c andhaving secured to its outer end a fingerc (see Fig. 1,) adjustably heldin position by a set-screw 10. The valve-actuator is shown as a swingingarm h, mounted to rock on the valve spindle between the finger c and theouter face of the extension and having at its upper end a weight H, thelower end of the actuator being bifurcated or forked to present twobranches It, provided each with a tappet or lug 7L2, the two tappetsbeing located on opposite sides of and to alternately cooperate with thefinger a I Referring to Fig. 1, if the actuator be swung from itsfull-line position'toward the right it will as soon as it passesdead-center be carried by gravity quickly into dotted line position, andthe righthand tappet h will engage and impart a quick blow to the fingerc to turn it from full to dotted line position, and thereby change theposition of the motor-valve 0 The initial movement of thevalve-actuator-that is, its movement from a, position of rest to justpast dead-center-is effected by or through a float F within the chamberA and governed as to its position The valve-chest (1' by the level ofthe compressing liquid in said chamber, the float being 'mounted on thefree end of an arm f, fulerumed atf on a lug or projection 0 dependingfrom the cylinder extension o said arm having branches f extendedupwardly and divergently from its fulcrum and preferably provided withfriction-rolls f (see Fig. 1,) located in the path of movement of and onopposite sides of the actuator h. By gradual movement of the float Ffrom full to dotted line position, Fig. 1, the left-hand roll f willswing the actuator into vertical position and then slightly beyonddead-center, the movement of the actuator past dead-center occurring ator about the time the liquid has risen to the proper height in thechamber, and after passing dead-center the weight II will complete theswinging movement of the actuator, as has been described, to change theposition of the motor-valve, On the other hand, afall in the level ofthe liquid will depress the float to descend until the right-hand roll fwill operate to swing the actuator from right to left, viewing Fig. 1,into vertical position and past dead-center, the completion of theswinging movement of the actuator being effected by its weight H.

I have shown in Fig. 1 a friction-block 7L4 secured to the actuator hand having 0ppositely beveled and divergent sides toward the fulcrum ofthe actuator, the rolls f engaging said beveled sides when impartingmove- I00 ment to the actuator.

In Figs. 1 and 2 the admission-port U is open and the valve V is seatedto close the outlet-port a of the compression-chamber,

and at such time the cylinder-port 4 will, by

means of the recess (3 in the valve 0 be in communication with theexhaust-passage c and port. 3 will be open to admit fluid to thecylinder C; but when the valve is shifted by movement of the actuatorfrom full to dotted no line position, Fig. 1, the valve 0 will be movedto open the cylinder-port 4 and to connect the port 3 with theexhaust-port, and a quick movement of the piston O will be effected tosimultaneously open the outlet-port 1 15 a, and close the admission-portb It is to be noted that in either position of the piston thecylinder-port which last admitted the actuating liquid to the cylinderremains open, so that the full pressure of the liquid is utilized to actupon the piston O and maintain the valves V V in desired positionentirely irrespective of any pressure within the compression-chamber,and in this connection it may be stated that the ports 3 and 4 opendirectly into the chamber 0 of the valve-chest, such chamber forming anenlargement of the passage or conduit .9.

The pipe or standard B is provided with a second conduit or passage 3Fig. 5, which 1 0 communicates at. its upper end with the eX-haust-passage c, and at its lower end it is connected by an extension 3Fig. 1', with the seal or trap T, the lower end of the extension isentirely unaffected by any pressure within the latter.

The pressure-reducing device hereinbefore referred to is interposedbetween the admission-port b of the compression-chamber and the branchor chamber 0 in the valve-case, which communicates with the cylinder ofthe hydraulic actuator through the ports 3 or 4, so that while thecylinder will receive the compressing liquid at its full pressure, dueto the head of the supply, the pressure of such liquid in thecompression-chamber will be less, due to the presence of thereducingvalve, so that a difierential pressure for the motor and thecompressing-chamber will be provided. I am thus enabled to operate thevalves V V against the pressure in the chamher by a comparatively small,yet powerful, actuator operated by the compressing liquid at fullpressure.

The throw of the weighted actuator is positively limited by means of apin 33, Fig. 1, extended rearwardly therefrom and adapted to engage oneor the other of two fixed projections 3st on the cylinder extension 0 Itis very desirable for many reasons to thoroughly wash the air in thecompressionchamber, so that when compressed the air will be very cleanand pure, and this washing is thoroughly effected by the apparatusherein shown.

The liquid-admission port 6 is downturned, as shown, and when said portis open the entering liquid impinges with considerable force, dependingupon the head of the supply, upon the top of the valve V and is thrownlaterally and upwardly in the form of finelydivided streams or spray.Such spray is thus brought into thorough and intimate contact with theair in the chamber, washing it and removing variousimpurities held insuspension by the incomingfresh air, such impurities being collected bythe spray and carried down to the main body of liquid in the chamher, tobe withdrawn therewith when the outlet-port is opened.

My invention is not restricted to the precise construction andarrangement herein shown and described, as the same may be modified andrearranged in various particulars without departing from the spirit andscope of my invention.

Having fully described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

1. In an aircompressor, a compressingchamber having admission anddischarge ports for the compressing liquid, cooperating valves,actuating mechanism therefor, including a hydraulic motor operated bythe compressing liquid, means to admit the liquid to the chamber at apressure lower than that acting upon the motor, and controlling meansfor the motor, governed by the level of the liquid in thecompressing-chamber.

2. In an air-compressor, a compressingchamber having admission anddischarge ports for the compressing liquid, cooperating valves,actuating mechanism therefor,incl uding a hydraulic motor, aliquid-supply conduit communicating with the motor and said admission-port, pressure-reducin g means interposed between the latter andthe liquidinlet for the motor, and controlling means for the motor,governed by the level of the liquid in the compressing-chamber.

3. In an air-compressor, a compressingchamber having admission anddischarge ports for the compressing liquid, cooperating valves,actuating mechanism theref0r,including a hydraulic motor, aliquid-supplycondnit communicating with the motor and saidadmission-port, pressure-reducing means interposed between the latterand the liquidinlet for the motor, an exhaust-passage leading from themotor and independent of the discharge-port of the chamber, andcontrolling means for the motor, governed by the level of the liquid inthe compressing-charm ber.

4:. In an air-compressor, a compressingchamber having admission anddischarge ports for the compressing liquid, cooperating and connectedvalves, to simultaneously open one and close the other of said ports, acylinder having a piston reciprocable therein and provided with ports atopposite ends thereof, the admission and discharge ports and theirvalves being wholly outside of the cylinder, a rigid connection betweenthe piston and the said valves to effect movement of the same in unison,mechanism to govern the inlet and exhaust of liquid to and from thecylinder, and actuating means for said mechanism, controlled by orthrough the level of the liquid in the compressing-chamber.

5. In an air-compressor, a compressingchamber having oppositely-locatedadmission and discharge ports for the compressing liquid,cooperatin gand rigidly-connected valves, valve-actuating mechanism, including acylinder having a piston reciprocable therein and provided with ports atits opposite ends, a piston-rod extended through the cylinder ends andconnected with said valves to constitute a rigid connectiontherebetween,mechanism to govern the admission and exhaust of liquid toand from the cylinder, to thereby move the piston to open one and closethe other of the controlling-valves for the chamber, and actuating meansfor said mechanism, controlled by or through the level of the liquid inthe compressing-chamber.

6. In an air-compressor, a compressingchamber having admission anddischarge ports for the compressing liquid, cooperating valves,valve-actuating mechanism, including a direct-acting hydraulic motor, adifier= ential-pressure connection between the liquid-supply and theadmission-port and the motor, to provide a higher pressure for operatingthe latter, and automatic controlling means for the motor, governed byor through the level of the liquid in the compressingchamber.

7. In an air compressor, a compressingchamber having admission anddischarge ports for the compressing liquid, cooperating valves andactuating means therefor, including a hydraulic motor, the latter andthe chamber having a common liquid-supply couduit, a pressure-reducerinterposed between the admission-port of the chamber and themotor-inlet, a liquid seal or trap into which the liquid is dischargedfrom the chamber, a separate exhaust-conduit for the motor, alsoconnected with the seal, and means governed by or through the level ofthe liquid in the chamber to effect intermitting operation of the motor.

8. In an aircompressor, a compressingchamber having a discharge-outletin its bottom, a liquid-inlet conduit extended upwardly into thechamber, and having a downturned port, to admit liquid therefrom in adownward stream directly into the upper part of the chamber, valvescooperating with said ports, the admission-valve being located directlybelow and movable toward and from the downturned port, the enteringliquid impinging on such cooperating valve when the admission-port isopen, to spray the liquid into the upper part of the chamber, and valveactuating mechanism controlled byor through the level of the liquid inthe chamber to antomatically open and close the admission and dischargeports alternately.

9. In an aircompressor, a compressingchamber, having admission anddischarge ports for the compressing liquid, cooperating valves,valve-actuating mechanism including a hydraulic motor, a liquid-inletconduit extended into the chamber and communicating with the saidadmission-port, areducing-valve adjacent the latter, a branch directlyconnecting the inlet-conduit with the valve-chest of the motor, and anexhaust-conduit for said motor independentof the chamber dischargeport,combined with controlling means for the motor including a float, wherebythe operation of the motor is governed by or through the level of theliquid in the compressingchamber.

10. In an air-compressor, a compressingchamber having oppositely-locatedadmission and discharge ports for the compressing liquid, cooperatingvalves, valve actuating mechanism including a hydraulic cylinderinterposed between said ports and having a reciprocable piston ofgreater cross-sectional area than either of said valves, a piston-rodoppositely extended through the cylinderheads and to which the valvesare secured, a valve-ch est having ports communicating with the oppositeends of the cylinder and provided with an exhaust-port, acontrollingvalve in said chest, means to operate said valve to effectthe movement of the piston in the cylinder in one or the otherdirection, said valve-chest being connected with the source of supply ofcompressing liquid, and a controller for said means including a floatWithin the chamber and governed as to its position by the level of theliquid therein.

11. In an air-compressor, a compressingchamber having admission andoutlet ports for the compressing liquid, valves codperating with saidports and movable directly toward and from them, and automaticvalveactuating mechanism, the admission-port be ing located in the upperpart of the chamber to deliver liquid directly thereinto, and itscooperating valve being at all times opposite and external to said port,the latter and its valve being located wholly exterior to thevalve-operating mechanism, whereby the liquid entering the chamberthrough the admission-port will impinge on the exposed admission-valvewhen the port is open to thereby forcibly spray the liquid in alldirections within the chamber.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

HERMAN STRATER;

/Vitnesses: I

JOHN C. EDWARns, AUGUSTA E. DEAN.

